JP5231357B2 - Resist material and pattern forming method using the same - Google Patents

Description

  The present invention relates to a resist material, particularly a chemically amplified positive resist material for electron beam (EB) exposure and vacuum ultraviolet light (EUV) exposure, and a pattern forming method using the same.

  With the high integration and high speed of LSI, pattern rule miniaturization is progressing rapidly. In particular, the expansion of the flash memory market and the increase in storage capacity are leading to miniaturization. The fine line for miniaturization is mass production of 65 nm node devices by ArF lithography, and preparation for mass production of 45 nm nodes by next generation ArF immersion lithography is in progress. Next generation 32nm node includes immersion lithography with ultra high NA lens combining liquid with higher refractive index than water, high refractive index lens and high refractive index resist, vacuum ultraviolet light (EUV) with wavelength of 13.5nm Lithography, double exposure of ArF lithography (double patterning lithography), and the like are candidates and are being studied.

  By the way, in recent years, the processing dimension is about to reach 50 nm as the minimum line width. However, when the processing dimension becomes so small, the structural strength to maintain the pattern against the surface tension of the developer, and the substrate The resist film thickness may need to be 100 nm or less depending on the surface material of the substrate to be processed due to factors such as adhesive strength, but it has been used to form a high resolution chemically amplified resist film. When a resist composition such as a base resin having an acetal-based protective group is used, the deterioration of the line edge roughness was not a major problem when the thickness of the chemically amplified resist film was 150 nm. When the thickness was 100 nm or less, there was a problem that the line edge roughness was greatly deteriorated.

Light elements such as hydrocarbons used in resists for high energy rays with very short wavelengths such as EB and X-rays hardly absorb, and polyhydroxystyrene-based resist materials have been studied.
The EB resist has been practically used for mask drawing. In recent years, mask manufacturing techniques have become a problem. A reduction projection exposure apparatus has been used since the light used for exposure was g-line, and its reduction magnification was 1/5. However, the magnification is 1/4 with the enlargement of the chip size and the enlargement of the projection lens. Therefore, the influence of the dimensional deviation of the mask on the dimensional change of the pattern on the wafer has become a problem. It has been pointed out that with the miniaturization of the pattern, the dimensional deviation on the wafer has become larger than the value of the dimensional deviation of the mask. There is a need for a mask error enhancement factor (MEEF) calculated using a mask dimensional change as a denominator and a dimensional change on a wafer as a numerator. It is not uncommon for MEEF to exceed 4 for 45 nm-class patterns. If the reduction ratio is 1/4 and the MEEF is 4, it can be said that the mask production requires the same accuracy as that of the substantially equal-size mask.
In order to increase the accuracy of the line width in the mask manufacturing exposure apparatus, an exposure apparatus using an electron beam (EB) has been used from an exposure apparatus using a laser beam. Furthermore, since further miniaturization is possible by increasing the acceleration voltage in the electron gun of EB, 10 keV to 30 keV, and recently 50 keV is the mainstream, and studies of 100 keV are also underway.

  Here, as the acceleration voltage increases, lowering the sensitivity of the resist has become a problem. When the acceleration voltage is improved, the influence of forward scattering in the resist film is reduced, so that the contrast of the electron drawing energy is improved and the resolution and dimensional controllability are improved. Since it passes, the sensitivity of the resist decreases. Since the mask exposure machine exposes by direct drawing with a single stroke, lowering the sensitivity of the resist leads to lower productivity, which is not preferable. Chemically amplified resists are being studied because of the demand for higher sensitivity.

  As miniaturization progresses, image blur due to acid diffusion has become a problem (Non-Patent Document 1). In order to ensure the resolution in a fine pattern with a size size of 45 nm or more, it is proposed that not only the conventionally proposed improvement in dissolution contrast but also the control of acid diffusion is important (Non-Patent Document). 2). However, chemically amplified resists have increased sensitivity and contrast due to acid diffusion, so if you try to minimize acid diffusion by shortening the post-exposure baking (PEB) temperature and time, the sensitivity and contrast are remarkably high. descend.

  It is effective to suppress acid diffusion by adding an acid generator that generates a bulky acid. Therefore, it has been proposed to copolymerize an acid generator of an onium salt having a polymerizable olefin with an acid generator. Patent Document 1, Patent Document 2, Patent Document 3 and the like propose a sulfonium salt and an iodonium salt having a polymerizable olefin that generates a specific sulfonic acid. Patent Document 4, Patent Document 5, Patent Document 6 and the like propose a sulfonium salt in which a sulfonic acid is directly bonded to the main chain.

  Further, in order to adjust sensitivity, a chemically amplified resist in which a polymer type amine compound is added as a quencher has been proposed. For example, Patent Document 7 includes polyvinyl pyridine, Patent Document 8 includes a positive resist to which dialkylethyl polymethacrylate or dialkylaminopropyl polystyrene is added, and Patent Document 9 includes an ArF immersion resist for copolymerizing a methacrylate having an amino group. Proposed.

A non-chemically amplified resist is low in sensitivity because of no decrease in contrast due to acid diffusion, but high resolution can be obtained. A positive resist using polymethyl methacrylate (PMMA) and a negative resist using hydrogen silsesquioxane (HSQ), which are representative of non-chemically amplified resists, are used to confirm the limit resolution of an EB lithography system. .
An example has been proposed in which sensitivity and resolution performance are balanced by a hybrid of a non-chemically amplified resist and a chemically amplified resist.

  Lithography (MAPPER) using countless low acceleration electron beams has been proposed (Non-patent Document 3). The acceleration voltage here is 5 keV, and when a normal chemically amplified resist is used, there is a problem that it is difficult to control the exposure amount because it is too sensitive. On the other hand, the non-chemically amplified resist is two orders of magnitude less sensitive than the chemically amplified resist. In this case, the sensitivity is too low to increase the throughput. There is a demand for a resist that is an order of magnitude less sensitive than a normal chemically amplified resist or an order of magnitude more sensitive than a non-chemically amplified resist. Chemically amplified resist can be reduced in sensitivity by increasing the amount of quencher added, but in order to reduce the sensitivity by an order of magnitude, a large amount of quencher will be added, and diffusion of amine quencher will increase. The resolution deteriorates due to the above. It has been reported that proximity bias changes not only by acid diffusion but also by amine diffusion (Non-Patent Document 4).

  Thus, with conventional resist materials, it is difficult to solve all the problems of resolution, sensitivity, and edge roughness. Therefore, early development of resist materials that can solve all these problems has been desired.

JP-A-4-230645 JP 2005-84365 A JP 2006-045311 A Patent 3613491 JP 2006-178317 A JP 2008-133448 A Japanese Patent Laid-Open No. 7-128859 Japanese Patent Laid-Open No. 9-292708 JP 2008-133312 A

SPIE Vol. 5039 p1 (2003) SPIE Vol. 6520 p65203L-1 (2007) SPIE Vol. 6521 p69211O-1 (2008) SPIE Vol. 4346 p319 (2001)

  The present invention has been made in view of the above circumstances, and is a resist material, particularly a chemically amplified positive resist material, which has high resolution and high sensitivity, and has a good pattern shape after exposure and small line edge roughness, and It is an object of the present invention to provide a pattern forming method used.

（式中、Ｒ^１、Ｒ^３、Ｒ^８、Ｒ^１２はそれぞれ独立に、水素原子、メチル基、フッ素原子、又は、トリフルオロメチル基を表す。Ｒ^２は酸不安定基を表す。Ｒ^４は炭素数１〜１０のアルキレン基又は炭素数６〜１０のアリーレン基であり、フッ素原子、トリフルオロメチル基、エステル基、エーテル基、ラクトン環を有していても良い。Ｒ^５、Ｒ^６、Ｒ^７、Ｒ^９、Ｒ^１０、Ｒ^１１は同一、又は異種の炭素数１〜１２の直鎖状、分岐状もしくは環状のアルキル基であり、カルボニル基、エステル基又はエーテル基を含んでいてもよく、又は炭素数６〜１２のアリール基、炭素数７〜２０のアラルキル基又はチオフェニル基を表し、炭素数１〜１０のアルキル基、アルコキシ基、アルコキシカルボニル基、カーボネート基、およびハロゲン原子、シアノ基、ヒドロキシル基、カルボキシル基を置換基として有していても良い。Ｙは単結合、メチレン基、フッ素原子もしくはトリフルオロメチル基で置換されたアリーレン基、−Ｃ（＝Ｏ）−Ｏ−Ｒ^１７−である。Ｒ^１７はフッ素原子もしくはトリフルオロメチル基で置換されたアリーレン基である。Ｒ^１３は単結合、又は炭素数１〜１０の直鎖状、分岐状もしくは環状のアルキレン基、Ｒ^１４、Ｒ^１５はそれぞれ独立に、水素原子、炭素数１〜２０直鎖状、分岐状もしくは環状のアルキル基、ｔ−ブトキシカルボニル基、又はｔ−アミロキシカルボニル基で、エーテル結合、チオエーテル結合、ヒドロキシル基、ホルミル基、アセトキシ基、シアノ基、芳香族基を有していてもよく、Ｒ^１３とＲ^１４、Ｒ^１３とＲ^１５、Ｒ^１４とＲ^１５がそれぞれ結合して環を形成していても良い。Ｒ^１６は水素原子又はＲ^１５と結合して環を形成していても良い。Ｚは単結合、メチレン基、アリーレン基、−Ｏ−、−Ｃ（＝Ｏ）−Ｏ−又は−Ｃ（＝Ｏ）−Ｏ−Ｒ^１８−Ｃ（＝Ｏ）−Ｏ−、である。Ｒ^１８は単結合、又は炭素数１〜１０の直鎖状、分岐状もしくは環状のアルキレン基である。０＜ａ＜１．０、０≦ｂ１≦０．３、０≦ｂ２≦０．３、０＜ｂ１＋ｂ２≦０．３、０＜ｃ≦０．５の範囲である。） In order to solve the above problems, the present invention includes at least a repeating unit a having a phenolic hydroxyl group substituted with an acid labile group represented by the following general formula (1), and repeating units b1 and b2 having a sulfonium salt. There is provided a resist material comprising any one or more of a polymer compound having a repeating unit c having an amino group.

(In the formula, R ¹ , R ³ , R ⁸ and R ¹² each independently represents a hydrogen atom, a methyl group, a fluorine atom or a trifluoromethyl group. R ² represents an acid labile group. R ⁴ Is an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 10 carbon atoms, and may have a fluorine atom, a trifluoromethyl group, an ester group, an ether group, or a lactone ring R ⁵ , R ⁶ , R ⁷ , R ⁹ , R ¹⁰ , R ¹¹ are the same or different, linear, branched or cyclic alkyl groups having 1 to 12 carbon atoms, including a carbonyl group, an ester group or an ether group. Or an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 20 carbon atoms or a thiophenyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group, an alkoxycarbonyl group, a carbonate group, and It may have a rogen atom, a cyano group, a hydroxyl group or a carboxyl group as a substituent, Y is a single bond, an arylene group substituted with a methylene group, a fluorine atom or a trifluoromethyl group, -C (= O) ^{-O-R 17} - is ^{.R 17} is fluorine atom or a substituted arylene group a trifluoromethyl group ^{.R 13} is a single bond or a straight, branched or cyclic alkylene ^group, R ^{14, R 15} are each independently a hydrogen atom, C 1 -C 20 straight, branched or cyclic alkyl group, t-butoxycarbonyl group, or t-a Mi butyloxycarbonyl group, an ether May have a bond, a thioether bond, a hydroxyl group, a formyl group, an acetoxy group, a cyano group, or an aromatic group; R ¹³ and R ¹⁴ , R ¹³ and R ^{1 5} , R ¹⁴ and R ¹⁵ may be bonded to each other to form a ring, R ¹⁶ may be bonded to a hydrogen atom or R ¹⁵ to form a ring, Z is a single bond, a methylene group, An arylene group, —O—, —C (═O) —O— or —C (═O) —O—R ¹⁸ —C (═O) —O—, wherein R ¹⁸ is a single bond or a carbon number; 1 to 10 linear, branched, or cyclic alkylene groups, 0 <a <1.0, 0 ≦ b1 ≦ 0.3, 0 ≦ b2 ≦ 0.3, 0 <b1 + b2 ≦ 0.3, 0 <c ≦ 0.5.)

  Such a resist material of the present invention includes, as a polymer compound constituting the resist material, a copolymer obtained by copolymerizing a repeating unit having an acid labile group, a polymer type acid generator, and a polymer type amine compound. Therefore, the high resolution and high sensitivity are obtained, the pattern shape after exposure is good, and the line edge roughness is small. Therefore, since it has these characteristics, it is very practical and is very effective as a resist material for VLSI or a mask pattern forming material.

In this case, the resist material is preferably a chemically amplified positive resist material.
As described above, the resist material containing the polymer compound has a polymer-type acid generator as the repeating units b1 and b2, and this generates an acid upon exposure to eliminate the acid labile group of the repeating unit a. Then, by converting the resist exposed portion so as to be dissolved in the developer, a chemically amplified positive resist material capable of obtaining a very high-precision pattern can be obtained.

  In this case, the resist material may contain any one or more of an organic solvent, a dissolution inhibitor, an acid generator, a basic compound, and a surfactant.

  Thus, by mix | blending an organic solvent, the applicability | paintability to the board | substrate etc. of a resist material can be improved, for example. Moreover, by mix | blending a dissolution inhibitor, the difference of the dissolution rate of an exposed part and an unexposed part can be enlarged further, and the resolution can be improved further. Further, by adding an acid generator, it can be made more sensitive. By blending the basic compound, the acid diffusion rate in the resist film can be suppressed and the resolution can be further improved. Furthermore, the application | coating property of a resist material can further be improved or controlled by mix | blending surfactant.

  Such a resist material of the present invention includes at least a step of applying the resist material on a substrate, a step of exposing to high energy rays after heat treatment, and a step of developing using a developer. It can be used as a method for forming a pattern on a semiconductor substrate, a mask substrate or the like.

  Needless to say, development may be performed after the post-exposure heat treatment, and various other processes such as an etching process, a resist removal process, and a cleaning process may be performed.

In this case, vacuum ultraviolet rays having a wavelength of 3 to 15 nm can be used as a light source in the step of exposing with the high energy rays.
As described above, the resist material of the present invention can be particularly suitably used for forming a fine pattern using a vacuum ultraviolet ray having a wavelength of 3 to 15 nm as a light source.

In the step of exposing with the high energy beam, an acceleration voltage electron beam having an acceleration voltage of 50 keV or less, particularly a low acceleration voltage electron beam having an acceleration voltage of 10 keV or less can be used as a light source.
As described above, the resist material of the present invention can be particularly suitably used for forming a fine pattern using an acceleration voltage electron beam having an acceleration voltage of 50 keV or less as a light source, and in particular, a low acceleration voltage of 10 keV or less. If an electron beam is used as a light source, there is almost no possibility of damaging the periphery of the exposure area during exposure.

  As described above, the resist material of the present invention has a significantly high alkali dissolution rate contrast before and after exposure, high sensitivity and high resolution, good pattern shape after exposure, and particularly acid diffusion. The speed is suppressed and the line edge roughness is small. Accordingly, a resist material suitable as a fine pattern forming material for VLSI manufacturing or a photomask, a pattern forming material for EB and EUV exposure, particularly a chemically amplified positive resist material can be obtained.

Hereinafter, the present invention will be described in more detail.
As described above, with the high integration and high speed of LSI, the pattern rule is becoming finer, so that the resolution is high but the sensitivity is high, the pattern shape after exposure is good, and the line edge roughness is small. There was a need for resist materials.

  As a result of intensive investigations to obtain a resist material having high resolution, high sensitivity, and low line edge roughness recently requested, the present inventors have found that a repeating unit having an acid labile group and a sulfonium having a polymerizable olefin. It has been found that it is extremely effective to use a polymer having a salt repeating unit and a repeating unit having an amino group as a base material of a resist material, particularly a chemically amplified positive resist material.

  More specifically, the present inventors have resisted a polymer obtained by copolymerization of a monomer having a phenolic hydroxyl group substituted with an acid labile group, a sulfonium salt monomer having a polymerizable olefin, and a monomer having an amino group. By using it as a base resin for materials, especially chemically amplified positive resist materials, the alkali dissolution rate contrast before and after exposure is high, acid diffusion and amine diffusion are suppressed, high resolution and high sensitivity, and the pattern shape after exposure is high. Completion of the present invention based on the knowledge that a resist material that exhibits good characteristics with low line edge roughness and that is suitable for ultra-LSI manufacturing or a photomask fine pattern forming material, especially a chemically amplified positive resist material, can be obtained. It has been made.

（式中、Ｒ^１、Ｒ^３、Ｒ^８、Ｒ^１２はそれぞれ独立に、水素原子、メチル基、フッ素原子、又はトリフルオロメチル基を表す。Ｒ^２は酸不安定基を表す。Ｒ^４は炭素数１〜１０のアルキレン基又は炭素数６〜１０のアリーレン基であり、フッ素原子、トリフルオロメチル基、エステル基、エーテル基、ラクトン環を有していても良い。Ｒ^５、Ｒ^６、Ｒ^７、Ｒ^９、Ｒ^１０、Ｒ^１１は同一、又は異種の炭素数１〜１２の直鎖状、分岐状もしくは環状のアルキル基であり、カルボニル基、エステル基又はエーテル基を含んでいてもよく、又は炭素数６〜１２のアリール基、炭素数７〜２０のアラルキル基又はチオフェニル基を表し、炭素数１〜１０のアルキル基、アルコキシ基、アルコキシカルボニル基、カーボネート基、およびハロゲン原子、シアノ基、ヒドロキシル基、カルボキシル基を置換基として有していても良い。Ｙは単結合、メチレン基、フッ素原子もしくはトリフルオロメチル基で置換されたアリーレン基、−Ｃ（＝Ｏ）−Ｏ−Ｒ^１７−である。Ｒ^１７はフッ素原子もしくはトリフルオロメチル基で置換されたアリーレン基である。Ｒ^１３は単結合、又は炭素数１〜１０の直鎖状、分岐状もしくは環状のアルキレン基、Ｒ^１４、Ｒ^１５はそれぞれ独立に、水素原子、炭素数１〜２０直鎖状、分岐状もしくは環状のアルキル基、ｔ−ブトキシカルボニル基、又はｔ−アミロキシカルボニル基で、エーテル結合、チオエーテル結合、ヒドロキシル基、ホルミル基、アセトキシ基、シアノ基、芳香族基を有していてもよく、Ｒ^１３とＲ^１４、Ｒ^１３とＲ^１５、Ｒ^１４とＲ^１５がそれぞれ結合して環を形成していても良い。Ｒ^１６は水素原子又はＲ^１５と結合して環を形成していても良い。Ｚは単結合、メチレン基、アリーレン基、−Ｏ−、−Ｃ（＝Ｏ）−Ｏ−又は−Ｃ（＝Ｏ）−Ｏ−Ｒ^１８−Ｃ（＝Ｏ）−Ｏ−、である。Ｒ^１８は単結合、又は炭素数１〜１０の直鎖状、分岐状もしくは環状のアルキレン基である。０＜ａ＜１．０、０≦ｂ１≦０．３、０≦ｂ２≦０．３、０＜ｂ１＋ｂ２≦０．３、０＜ｃ≦０．５の範囲である。） That is, the resist material of the present invention is at least one of the repeating unit a having a phenolic hydroxyl group substituted with an acid labile group and the repeating units b1 and b2 having a sulfonium salt represented by the following general formula (1). It includes a polymer compound having at least one repeating unit c having an amino group.

(In the formula, R ¹ , R ³ , R ⁸ and R ¹² each independently represents a hydrogen atom, a methyl group, a fluorine atom or a trifluoromethyl group. R ² represents an acid labile group. R ⁴ represents an alkylene group or an arylene group having 6 to 10 carbon atoms having 1 to 10 carbon atoms, a fluorine atom, a trifluoromethyl group, an ester group, an ether group, which may have a lactone ring ^{.R 5, R} 6, R ⁷ , R ⁹ , R ¹⁰ and R ¹¹ are the same or different, linear, branched or cyclic alkyl groups having 1 to 12 carbon atoms, and may contain a carbonyl group, an ester group or an ether group. Or an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or a thiophenyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group, an alkoxycarbonyl group, a carbonate group, and May have a gen atom, a cyano group, a hydroxyl group, or a carboxyl group as a substituent, Y is a single bond, an methylene group, an arylene group substituted with a fluorine atom or a trifluoromethyl group, -C (= O) ^{-O-R 17} - is ^{.R 17} is fluorine atom or a substituted arylene group a trifluoromethyl group ^{.R 13} is a single bond or a straight, branched or cyclic alkylene ^group, R ^{14, R 15} are each independently a hydrogen atom, C 1 -C 20 straight, branched or cyclic alkyl group, t-butoxycarbonyl group, or t-a Mi butyloxycarbonyl group, an ether May have a bond, a thioether bond, a hydroxyl group, a formyl group, an acetoxy group, a cyano group or an aromatic group, and R ¹³ and R ¹⁴ , R ¹³ and R ¹⁵ R ¹⁴ and R ¹⁵ may be bonded to form a ring, R ¹⁶ may be bonded to a hydrogen atom or R ¹⁵ to form a ring, and Z is a single bond, methylene group, arylene. A group, —O—, —C (═O) —O— or —C (═O) —O—R ¹⁸ —C (═O) —O—, wherein R ¹⁸ is a single bond or 1 carbon atom. A linear, branched or cyclic alkylene group of from 0 to 10. 0 <a <1.0, 0 ≦ b1 ≦ 0.3, 0 ≦ b2 ≦ 0.3, 0 <b1 + b2 ≦ 0.3, 0 <C ≦ 0.5.)

  Such a resist material of the present invention has a repeating unit a, thereby forming a fine pattern having a good shape with a high resolution and a small line edge roughness even when exposed to a high energy ray having a short wavelength. Since the polymer-type acid generator shown in the repeating units b1 and b2 has an acid generator during the exposure, the acid leaving group of the repeating unit a is eliminated to develop the resist exposed portion. By converting so as to be dissolved in a liquid, it is possible to obtain a very high-precision pattern, and by having a polymer-type amine compound shown in the repeating unit c, it is possible to prevent a decrease in light contrast and sensitivity, and as a result. A pattern having a good shape can be obtained even at the resolution limit.

Therefore, the resist material of the present invention has particularly high resist film dissolution contrast, high resolution, exposure margin, excellent process adaptability, high sensitivity, and good pattern shape after exposure. The line edge roughness is small. Therefore, since it has these excellent characteristics, it is extremely practical and is very effective as a resist material for VLSI.
The above-described resist materials of the present invention, particularly chemically amplified positive resist materials, can be used not only for lithography in semiconductor circuit formation, but also for mask circuit pattern formation, micromachines, and thin film magnetic head circuits. It can be applied to formation and the like.

（式中、Ｒ^１、Ｒ^２は前述と同様である。） Among the repeating units contained in the polymer compound according to the present invention, the repeating unit having an acid labile group represented by the repeating unit a in the general formula (1) is a phenolic hydroxyl group, preferably a hydroxyl group of hydroxystyrene. These are substituted hydrogen atoms, and can be specifically exemplified below.

(Wherein R ¹ and R ² are the same as described above.)

The acid labile group represented by R ² is variously selected and may be the same or different, and in particular, those represented by the groups substituted by the following formulas (A-1) to (A-3) can be mentioned. .

In the above formula (A-1), R ³⁰ is a tertiary alkyl group having 4 to 20 carbon atoms, preferably 4 to 15 carbon atoms, each alkyl group is a trialkylsilyl group having 1 to 6 carbon atoms, and 4 to 20 carbon atoms. Or a group represented by the above general formula (A-3), specifically, as the tertiary alkyl group, a tert-butyl group, a tert-amyl group, a 1,1-diethylpropyl group, 1- Ethylcyclopentyl group, 1-butylcyclopentyl group, 1-ethylcyclohexyl group, 1-butylcyclohexyl group, 1-ethyl-2-cyclopentenyl group, 1-ethyl-2-cyclohexenyl group, 2-methyl-2-adamantyl group Specific examples of the trialkylsilyl group include a trimethylsilyl group, a triethylsilyl group, a dimethyl-tert-butylsilyl group, and the like. It is, specifically oxoalkyl group, 3-oxo-cyclohexyl group, 4-methyl-2-oxooxan-4-yl group, and 5-methyl-2-oxooxolan-5-yl group. a1 is an integer of 0-6.

  Specific examples of the acid labile group of the above formula (A-1) include tert-butoxycarbonyl group, tert-butoxycarbonylmethyl group, tert-amyloxycarbonyl group, tert-amyloxycarbonylmethyl group, 1,1 -Diethylpropyloxycarbonyl group, 1,1-diethylpropyloxycarbonylmethyl group, 1-ethylcyclopentyloxycarbonyl group, 1-ethylcyclopentyloxycarbonylmethyl group, 1-ethyl-2-cyclopentenyloxycarbonyl group, 1-ethyl Examples include 2-cyclopentenyloxycarbonylmethyl group, 1-ethoxyethoxycarbonylmethyl group, 2-tetrahydropyranyloxycarbonylmethyl group, 2-tetrahydrofuranyloxycarbonylmethyl group and the like.

Furthermore, the substituent shown by following formula (A-1) -1-(A-1) -10 can also be mentioned.

Here, R ³⁷ is the same or different from each other, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms, R ³⁸ is a hydrogen atom, or 1 to 1 carbon atoms. 10 linear, branched or cyclic alkyl groups.
R ³⁹ is a linear, branched or cyclic alkyl group having 2 to 10 carbon atoms which is the same or different from each other, or an aryl group having 6 to 20 carbon atoms.

In the above formula (A-2), R ³¹ and R ³² represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 18, preferably 1 to 10 carbon atoms, specifically a methyl group. , Ethyl group, propyl group, isopropyl group, n-butyl group, sec-butyl group, tert-butyl group, cyclopentyl group, cyclohexyl group, 2-ethylhexyl group, n-octyl group and the like. R ³³ represents a monovalent hydrocarbon group which may have a hetero atom such as an oxygen atom having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms, a linear, branched or cyclic alkyl group, Examples include those in which a part of hydrogen atoms are substituted with a hydroxyl group, an alkoxy group, an oxo group, an amino group, an alkylamino group, and the like, and specific examples include the following substituted alkyl groups.

R ³¹ and R ^32, R ³¹ and R ^33, R ³² and the R ³³ may bond together to form a ring with the carbon atoms to which they are attached, R ³¹ in the case of forming a ring, R ^32, R ³³ represents a linear or branched alkylene group having 1 to 18 carbon atoms, preferably 1 to 10 carbon atoms, and preferably the ring has 3 to 10 carbon atoms, particularly 4 to 10 carbon atoms.

  Of the acid labile groups represented by the above formula (A-2), examples of the linear or branched groups include those of the following formulas (A-2) -1 to (A-2) -72. be able to.

  Among the acid labile groups represented by the above formula (A-2), the cyclic ones include tetrahydrofuran-2-yl group, 2-methyltetrahydrofuran-2-yl group, tetrahydropyran-2-yl group, 2- Examples thereof include a methyltetrahydropyran-2-yl group.

  Further, the base resin may be intermolecularly or intramolecularly crosslinked by an acid labile group represented by the following general formula (A-2a) or (A-2b).

In the formula, R ⁴⁰ and R ⁴¹ represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 8 carbon atoms. Alternatively, R ⁴⁰ and R ⁴¹ may be bonded to form a ring together with the carbon atom to which they are bonded. When forming a ring, R ⁴⁰ and R ⁴¹ are linear or branched having 1 to 8 carbon atoms. -Like alkylene group. R ⁴² is a straight-chain having 1 to 10 carbon atoms, branched or cyclic alkylene group, b3, d1 is 0 or 1 to 10, preferably 0 or an integer of 1 to 5, c1 is an integer of 1-7 . A represents a (c1 + 1) -valent aliphatic or alicyclic saturated hydrocarbon group having 1 to 50 carbon atoms, an aromatic hydrocarbon group or a heterocyclic group, and these groups may intervene a hetero atom, Alternatively, a part of hydrogen atoms bonded to the carbon atom may be substituted with a hydroxyl group, a carboxyl group, a carbonyl group, or a fluorine atom. B represents —CO—O—, —NHCO—O— or —NHCONH—.

  In this case, preferably, A is a divalent to tetravalent C1-20 linear, branched or cyclic alkylene group, an alkyltriyl group, an alkyltetrayl group, or an arylene group having 6 to 30 carbon atoms. In these groups, a hetero atom may be interposed, and a part of hydrogen atoms bonded to the carbon atom may be substituted with a hydroxyl group, a carboxyl group, an acyl group, or a halogen atom. C1 is preferably an integer of 1 to 3.

  Specific examples of the crosslinked acetal groups represented by the general formulas (A-2a) and (A-2b) include those represented by the following formulas (A-2) -100 to (A-2) -107.

Next, in the above formula (A-3), R ³⁴ , R ³⁵ and R ³⁶ are each independently a hydrogen atom, a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, an aryl group, an alkenyl group. A monovalent hydrocarbon group such as oxygen, sulfur, nitrogen, fluorine, etc., and R ³⁴ and R ³⁵ , R ³⁴ and R ³⁶ , and R ³⁵ and R ³⁶ are bonded to each other. A ring having 3 to 20 carbon atoms may be formed together with the carbon atom to which is bonded.

  As the tertiary alkyl group represented by the above formula (A-3), a tert-butyl group, a triethylcarbyl group, a 1-ethylnorbornyl group, a 1-methylcyclohexyl group, a 1-ethylcyclopentyl group, 2- (2 -Methyl) adamantyl group, 2- (2-ethyl) adamantyl group, tert-amyl group and the like.

Specific examples of the tertiary alkyl group include the following formulas (A-3) -1 to (A-3) -18.

In the above formulas (A-3) -1 to (A-3) -18, R ⁴³ is the same or different, linear, branched or cyclic alkyl group having 1 to 8 carbon atoms, or 6 to 20 carbon atoms. An aryl group such as a phenyl group or a naphthyl group. R ⁴⁴ and R ⁴⁶ represent a hydrogen atom or a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms. R ⁴⁵ represents an aryl group such as a phenyl group having 6 to 20 carbon atoms.

Furthermore, as shown in the following formulas (A-3) -19 and (A-3) -20, a divalent or higher valent alkylene group and an arylene group R ⁴⁷ are included, and the polymer within or between the molecules is crosslinked. May be.

In the above formulas (A-3) -19 and (A-3) -20, R ⁴³ is the same as described above, and R ⁴⁷ is a linear, branched or cyclic alkylene group having 1 to 20 carbon atoms, or a phenylene group. An arylene group such as an oxygen atom, a sulfur atom, or a nitrogen atom. e1 is an integer of 1 to 3.

R ³⁰ , R ³³ and R ³⁶ in the above formulas (A-1), (A-2) and (A-3) are a phenyl group, a p-methylphenyl group, a p-ethylphenyl group and a p-methoxyphenyl. An unsubstituted or substituted aryl group such as an alkoxy-substituted phenyl group, an aralkyl group such as a benzyl group or a phenethyl group, or the like. Or an alkyl group represented by the following formula in which two hydrogen atoms are substituted with an oxygen atom to form a carbonyl group, or an oxoalkyl group.

The monomer for obtaining the repeating unit b1 which has a sulfonium salt in the said General formula (1) can be specifically illustrated below.

Specific examples of the monomer for obtaining the repeating unit b2 having the sulfonium salt in the general formula (1) can be given below.

The monomer for obtaining the repeating unit which has an amino group represented by the repeating unit c in the said General formula (1) can be specifically illustrated below.
Here, R ¹² is the same as described above.

  The present invention comprises copolymerizing a repeating unit a having a phenolic hydroxyl group substituted with an acid labile group, one or more of repeating units b1 and b2 having a sulfonium salt, and a repeating unit c having an amino group. Further, it is possible to copolymerize a repeating unit d having a phenolic hydroxyl group as an adhesive group.

The monomer for obtaining the repeating unit d which has a phenolic hydroxyl group can be specifically shown below.

  Furthermore, as another adhesive group, a repeating unit e of an adhesive group having a hydroxyl group, a lactone ring, an ether group, an ester group, a carbonyl group, or a cyano group can be copolymerized, and as a monomer for obtaining e Specifically, can be exemplified below.

  In the case of a monomer having a hydroxyl group, the hydroxyl group may be replaced with an acetal that can be easily deprotected with an acid such as ethoxyethoxy during the polymerization, and then deprotected with a weak acid and water after the polymerization, or an acetyl group or a formyl group. Alternatively, it may be substituted with a pivaloyl group or the like and subjected to alkali hydrolysis after polymerization.

Indene, benzofuran, benzothiophene, acenaphthylene, chromone, coumarin, norbornadiene and their derivatives f can also be copolymerized, specifically exemplified below.

  Examples of the repeating unit g that can be copolymerized in addition to the above repeating units include styrene, vinyl naphthalene, vinyl anthracene, vinyl pyrene, and methylene indane.

  The copolymerization ratios of a, b1, b2, c, d, e, f, and g are as follows: 0 <a <1.0, 0 ≦ b1 ≦ 0.3, 0 ≦ b2 ≦ 0.3, 0 <b1 + b2 ≦ 0 .3, 0 <c ≦ 0.5, 0 ≦ d ≦ 0.9, 0 ≦ e ≦ 0.9, 0 ≦ f ≦ 0.5, 0 ≦ g ≦ 0.5, preferably 0.1 ≦ a ≦ 0.8, 0 ≦ b1 ≦ 0.25, 0 ≦ b2 ≦ 0.25, 0.01 ≦ b1 + b2 ≦ 0.25, 0 <c ≦ 0.4, 0 ≦ d ≦ 0.8, 0 ≦ e ≦ 0.8, 0 ≦ f ≦ 0.4, 0 ≦ g ≦ 0.4, more preferably 0.15 ≦ a ≦ 0.7, 0 ≦ b1 ≦ 0.2, 0 ≦ b2 ≦ 0. 2, 0.02 ≦ b1 + b2 ≦ 0.25, 0 <c ≦ 0.3, 0 ≦ d ≦ 0.75, 0 ≦ e ≦ 0.75, 0 ≦ f ≦ 0.3, 0 ≦ g ≦ 0. 3.

  In order to synthesize these polymer compounds, as one method, for example, monomers represented by the repeating units a to c and d to g are subjected to heat polymerization in an organic solvent by adding a radical polymerization initiator, A combined polymer compound can be obtained.

  Examples of the organic solvent used at the time of polymerization include toluene, benzene, tetrahydrofuran, diethyl ether, dioxane and the like. As polymerization initiators, 2,2′-azobisisobutyronitrile (AIBN), 2,2′-azobis (2,4-dimethylvaleronitrile), dimethyl 2,2-azobis (2-methylpropionate) ), Benzoyl peroxide, lauroyl peroxide and the like, and preferably polymerized by heating to 50 to 80 ° C. The reaction time is 2 to 100 hours, preferably 5 to 20 hours.

  When copolymerizing hydroxystyrene and hydroxyvinylnaphthalene, acetoxystyrene and acetoxyvinylnaphthalene are used in place of hydroxystyrene and hydroxyvinylnaphthalene, and after polymerization, the acetoxy group is deprotected by the above alkaline hydrolysis to produce polyhydroxystyrene and hydroxyhydroxyl. There is also a method of making polyvinyl naphthalene.

  Ammonia water, triethylamine, etc. can be used as the base during the alkali hydrolysis. The reaction temperature is −20 to 100 ° C., preferably 0 to 60 ° C., and the reaction time is 0.2 to 100 hours, preferably 0.5 to 20 hours.

  The polymer compound used in the resist material of the present invention has a weight average molecular weight of 1,000 to 500,000, preferably 2,000 to 30,000, respectively. If the weight average molecular weight is 1,000 or more, the resist material has excellent heat resistance. If the weight average molecular weight is 500,000 or less, the alkali solubility does not decrease, and a trailing phenomenon may occur after pattern formation. Absent.

  Further, in the polymer compound used in the resist material of the present invention, when the molecular weight distribution (Mw / Mn) of the multi-component copolymer is wide, there is a low molecular weight or high molecular weight polymer. Foreign matter is seen on the top or the shape of the pattern is deteriorated. Therefore, since the influence of such molecular weight and molecular weight distribution tends to increase as the pattern rule becomes finer, in order to obtain a resist material suitably used for fine pattern dimensions, the multi-component copolymer to be used is obtained. The molecular weight distribution is preferably from 1.0 to 2.0, particularly preferably from 1.0 to 1.5 and narrow dispersion.

  The polymer compound used in the resist material of the present invention includes a repeating unit a in which a hydrogen atom of a phenolic hydroxyl group is substituted with an acid labile group, a repeating unit b having a sulfonium salt (any one or more of b1 and b2), Although it has the repeating unit c which has an amino group, it is also possible to blend two or more polymers from which a composition ratio, molecular weight distribution, and molecular weight differ. In order to adjust the sensitivity, the polymer compound having the repeating unit a, the repeating unit b, and the repeating unit c is further replaced with, for example, a repeating unit in which a hydrogen atom of a phenolic hydroxyl group is substituted with an acid labile group, A polymer compound having a repeating unit having a sulfonium salt of fluorosulfonic acid bonded to the main chain can also be blended.

  The polymer compound according to the present invention is particularly suitable as a base resin for a positive resist material. Such a polymer compound is used as a base resin, and an organic solvent, an acid generator, a dissolution inhibitor, a basic compound, an interface By combining the activator and the like appropriately in accordance with the purpose to form a positive resist material, the dissolution rate of the polymer compound in the developing solution is accelerated by a catalytic reaction in the exposed area, so that a highly sensitive positive resist is formed. Type resist material, resist film with high dissolution contrast and resolution, exposure margin, excellent process adaptability, good pattern shape after exposure, and better etching resistance In particular, the acid-diffusion can be suppressed, so the density difference is small. It can be a valid one. In particular, when a chemically amplified positive resist material containing an acid generator and utilizing an acid catalyzed reaction is used, the sensitivity can be increased, and various characteristics are further improved and extremely useful. .

  Further, by adding a dissolution inhibitor to the positive resist material, the difference in dissolution rate between the exposed portion and the unexposed portion can be further increased, and the resolution can be further improved.

  Furthermore, by adding a basic compound, for example, the acid diffusion rate in the resist film can be suppressed to further improve the resolution, and by adding a surfactant, the coatability of the resist material can be further improved. Alternatively, it can be controlled.

As described above, the resist material of the present invention may contain an acid generator for causing the chemically amplified positive resist material used in the pattern forming method of the present invention to function. For example, the resist material is sensitive to actinic rays or radiation. You may contain the compound (photo acid generator) which generate | occur | produces an acid. The component of the photoacid generator may be any compound that generates an acid upon irradiation with high energy rays. Suitable photoacid generators include sulfonium salts, iodonium salts, sulfonyldiazomethane, N-sulfonyloxyimide, oxime-O-sulfonate type acid generators, and the like.
Specific examples of the acid generator are described, for example, in paragraphs [0122] to [0142] of JP-A-2008-111103. These can be used alone or in admixture of two or more.

Specific examples of the organic solvent that can be blended in the resist material of the present invention include, for example, paragraphs [0144] to [0145] of JP-A-2008-111103, and paragraphs [0146] to [0164] as basic compounds. The surfactants are described in paragraphs [0165] to [0166], and the dissolution control agent is described in paragraphs [0155] to [0178] of JP-A-2008-122932. A polymer-type quencher described in JP-A-2008-239918 can also be added. Furthermore, acetylene alcohols can be added as an optional component as necessary, and specific examples of acetylene alcohols are described in paragraphs [0179] to [0182] of JP-A-2008-122932.
These enhance the rectangularity of the resist after patterning by being oriented on the resist surface after coating. The polymer quencher also has an effect of preventing pattern film loss and pattern top rounding when a protective film for immersion exposure is applied.

  The present invention also includes a pattern forming method comprising: a step of applying the resist material onto a substrate; a step of exposing to high energy rays after heat treatment; and a step of developing using a developer. I will provide a.

  In this case, in the step of exposing with the high energy beam, vacuum ultraviolet rays having a wavelength of 3 to 15 nm, an acceleration voltage electron beam having an acceleration voltage of 50 keV or less, particularly a low acceleration voltage electron beam of 10 keV or less can be used as a light source.

  When the resist material of the present invention, for example, a chemically amplified positive resist material containing an organic solvent, the polymer compound represented by the above general formula (1), an acid generator, and a basic compound is used for manufacturing various integrated circuits Although not particularly limited, a known lithography technique can be applied.

For example, the resist material of the present invention is applied to a substrate for manufacturing an integrated circuit or a layer to be processed on the substrate (Si, SiO ₂ , SiN, SiON, TiN, WSi, BPSG, SOG, organic antireflection film, etc.), mask Appropriate coating such as spin coating, roll coating, flow coating, dip coating, spray coating, doctor coating, etc. on a circuit manufacturing substrate or a layer to be processed on the substrate (Cr, CrO, CrON, MoSi, SiO _2, etc.) It is applied so that the coating film thickness is 0.1 to 2.0 μm by a method. This is pre-baked on a hot plate at 60 to 150 ° C. for 10 seconds to 30 minutes, preferably 80 to 120 ° C. for 30 seconds to 20 minutes.

Next, a target pattern is passed through a predetermined mask with a light source selected from high energy rays such as ultraviolet rays, far ultraviolet rays, electron beams, X-rays, excimer lasers, γ rays, synchrotron radiation, and vacuum ultraviolet rays (soft X-rays). Direct exposure is performed. It is preferable to expose so that the exposure amount is about 1 to 200 mJ / cm ² , preferably 10 to 100 mJ / cm ² , or 0.1 to 100 μC, and preferably about 0.5 to 50 μC. Next, post-exposure baking (PEB) is performed on a hot plate at 60 to 150 ° C. for 10 seconds to 30 minutes, preferably 80 to 120 ° C. for 30 seconds to 20 minutes.

  Further, 0.1 to 5% by mass, preferably 2 to 3% by mass of a developer of an alkaline aqueous solution such as tetramethylammonium hydroxide (TMAH) is used for 3 seconds to 3 minutes, preferably 5 seconds to 2 minutes. By developing by a conventional method such as a dip method, a paddle method, or a spray method, a portion irradiated with light is dissolved in the developer, and a portion not exposed to light is not dissolved. The desired positive pattern is formed on the top.

The resist material of the present invention is most suitable for fine patterning using electron beams, vacuum ultraviolet rays (soft X-rays), X-rays, γ rays, and synchrotron radiation among high energy rays.
In particular, if a vacuum ultraviolet ray having a wavelength of 3 to 15 nm or an acceleration voltage electron beam having an acceleration voltage of 50 keV or less, particularly a low acceleration voltage electron beam having an acceleration voltage of 10 keV or less is used as a light source, a finer pattern can be formed.

  EXAMPLES Hereinafter, although a synthesis example, a comparative synthesis example, an Example, and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example.

[Synthesis Example 1]
In a 2 L flask, 5.3 g of 4-t-butoxystyrene, 7.3 g of 4-acetoxystyrene, 3-oxo-2,7-dioxatricyclomethacrylate [4.2.1.0 ^4,8 ] nonane- 3.4 g of 9-yl, 4.5 g of PAG monomer 3, 0.4 g of 1-vinylimidazole, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
4-t-butoxystyrene: 4-hydroxystyrene: 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonan-9-yl methacrylate: PAG monomer 3: 1- Vinylimidazole = 0.30: 0.43: 0.15: 0.08: 0.04
Weight average molecular weight (Mw) = 8,200
Molecular weight distribution (Mw / Mn) = 1.96
This polymer compound is designated as Polymer 1.

[Synthesis Example 2]
In a 2 L flask, 5.7 g of 4-t-amyloxystyrene, 7.6 g of 4-acetoxystyrene, 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonane methacrylate 2.2 g of -9-yl, 4.6 g of PAG monomer 2, 0.8 g of 2-piperidinoethyl methacrylate, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
4-t-amyloxystyrene: 4-hydroxystyrene: 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonan-9-yl methacrylate: PAG monomer 2: methacryl 2-piperidinoethyl acid = 0.30: 0.48: 0.10: 0.08: 0.04
Weight average molecular weight (Mw) = 7,300
Molecular weight distribution (Mw / Mn) = 1.71
This polymer compound is designated as Polymer 2.

[Synthesis Example 3]
In a 2 L flask, 5.7 g of 4-t-amyloxystyrene, 8.1 g of 4-hydroxyphenyl methacrylate, 3-oxo-2,7-dioxatricyclomethacrylate [4.2.1.0 ^4,8 ] 3.3 g of nonan-9-yl, 4.5 g of PAG monomer 3, 0.8 g of 2-piperidinoethyl methacrylate, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution was precipitated in 1 L of isopropyl alcohol, and the resulting white solid was filtered and dried under reduced pressure at 60 ° C. to obtain a white polymer.
When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
4-t-amyloxystyrene: 4-hydroxyphenyl methacrylate: 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonan-9-yl methacrylate: PAG monomer 3 : 2-piperidinoethyl methacrylate = 0.30: 0.43: 0.15: 0.08: 0.04
Weight average molecular weight (Mw) = 7,400
Molecular weight distribution (Mw / Mn) = 1.79
This polymer compound is designated as Polymer 3.

[Synthesis Example 4]
In a 2 L flask, 4-t-amyloxystyrene 5.7, methacrylic acid 5-hydroxyindan-2-yl 9.4 g, methacrylic acid 3-oxo-2,7-dioxatricyclo [4.2.1. ^0,8 ] nonane-9-yl, 3.3 g of PAG monomer 3, 0.6 g of N, N-dimethyl-4-vinylaniline, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution was precipitated in 1 L of isopropyl alcohol, and the resulting white solid was filtered and dried under reduced pressure at 60 ° C. to obtain a white polymer.
When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
4-t-amyloxystyrene: 5-hydroxyindan-2-yl methacrylate: 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonan-9-yl methacrylate : PAG monomer 3: N, N-dimethyl-4-vinylaniline = 0.30: 0.43: 0.15: 0.08: 0.04
Weight average molecular weight (Mw) = 7,500
Molecular weight distribution (Mw / Mn) = 1.73
This polymer compound is designated as polymer 4.

[Synthesis Example 5]
In a 2 L flask, 5.7 g of 4-t-amyloxystyrene, 9.8 g of 6-hydroxynaphthalen-2-yl methacrylate, 2.6 g of tetrahydro-2-oxofuran-3-yl methacrylate, 4 of PAG monomer 3 0.5 g, 4-vinylamine 0.2 g, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution was precipitated in 1 L of isopropyl alcohol, and the resulting white solid was filtered and dried under reduced pressure at 60 ° C. to obtain a white polymer.
When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
4-t-amyloxystyrene: 6-hydroxynaphthalen-2-yl methacrylate: tetrahydro-2-oxofuran-3-yl methacrylate: PAG monomer 3: 4-vinylamine = 0.30: 0.43: 0. 15: 0.08: 0.04
Weight average molecular weight (Mw) = 8,200
Molecular weight distribution (Mw / Mn) = 1.76
This polymer compound is designated as polymer 5.

[Synthesis Example 6]
To a 2 L flask, 9.8 g of monomer 1, 9.4 g of 4-acetoxystyrene, 4.5 g of PAG monomer 3, 0.5 g of indole, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 1: 4-hydroxystyrene: PAG monomer 3: Indole = 0.30: 0.58: 0.08: 0.04
Weight average molecular weight (Mw) = 5,600
Molecular weight distribution (Mw / Mn) = 1.69
This polymer compound is designated as polymer 6.

[Synthesis Example 7]
To a 2 L flask, 8.8 g of monomer 2, 9.7 g of 4-acetoxystyrene, 2.9 g of PAG monomer 3, 0.5 g of 6-hydroxyindole, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: 4-hydroxystyrene: PAG monomer 3: 6-hydroxyindole = 0.28: 0.60: 0.08: 0.04
Weight average molecular weight (Mw) = 6,300
Molecular weight distribution (Mw / Mn) = 1.63
This polymer compound is designated as polymer 7.

[Synthesis Example 8]
To a 2 L flask was added 8.3 g of monomer 3, 9.7 g of 4-acetoxystyrene, 4.5 g of PAG monomer 3, 0.8 g of 2-vinylcarbazole, and 40 g of tetrahydrofuran as a solvent. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 3: 4-hydroxystyrene: PAG monomer 3: 2-vinylcarbazole = 0.28: 0.60: 0.08: 0.04
Weight average molecular weight (Mw) = 8,100
Molecular weight distribution (Mw / Mn) = 1.91
This polymer compound is designated as polymer 8.

[Synthesis Example 9]
To a 2 L flask, 40 g of tetrahydrofuran was added as a solvent for 8.7 g of monomer 4, 9.7 g of 4-acetoxystyrene, 4.5 g of PAG monomer 3, and 0.8 g of 9-vinylcarbazole. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 4: 4-hydroxystyrene: PAG monomer 3: 9-vinylcarbazole = 0.28: 0.60: 0.08: 0.04
Weight average molecular weight (Mw) = 8,300
Molecular weight distribution (Mw / Mn) = 1.79
This polymer compound is designated as polymer 9.

[Synthesis Example 10]
To a 2 L flask was added 9.6 g of monomer 5, 9.7 g of 4-acetoxystyrene, 4.5 g of PAG monomer 3, 0.6 g of 6-cyanoindole, and 40 g of tetrahydrofuran as a solvent. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 5: 4-hydroxystyrene: PAG monomer 3: 6-cyanoindole = 0.28: 0.60: 0.08: 0.04
Weight average molecular weight (Mw) = 6,700
Molecular weight distribution (Mw / Mn) = 1.77
This polymer compound is designated as polymer 10.

[Synthesis Example 11]
In a 2 L flask, 6.6 g of monomer 6, 1.5 g of coumarin, 10.0 g of 4-acetoxystyrene, 3.0 g of PAG monomer 2, 0.3 g of 1-vinyl-1,2,4-triazole, tetrahydrofuran as a solvent 40 g of was added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 6: Coumarin: 4-Hydroxystyrene: PAG Monomer 2: 1-Vinyl-1,2,4-triazole = 0.20: 0.10: 0.62: 0.05: 0.03
Weight average molecular weight (Mw) = 7,100
Molecular weight distribution (Mw / Mn) = 1.79
This polymer compound is designated as polymer 11.

[Synthesis Example 12]
To a 2 L flask, 9.5 g of monomer 2, 9.7 g of 4-acetoxystyrene, 3.4 g of PAG monomer 3, 1.0 g of coumarin 6H, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: Methacrylic acid-3-ethyl-3-exotetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodecanyl: 4-hydroxystyrene: PAG monomer 3: coumarin 6H = 0.30: 0.60: 0.06: 0.04
Weight average molecular weight (Mw) = 7,500
Molecular weight distribution (Mw / Mn) = 1.82
This polymer compound is designated as polymer 12.

[Synthesis Example 13]
9.5 g of monomer 2, 9.7 g of 4-acetoxystyrene, 3.4 g of PAG monomer 3, 1.0 g of coumarin 466, and 40 g of tetrahydrofuran as a solvent were added to a 2 L flask. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: 4-hydroxystyrene: PAG monomer 3: Coumarin 466 = 0.30: 0.60: 0.06: 0.04
Weight average molecular weight (Mw) = 8,200
Molecular weight distribution (Mw / Mn) = 1.77
This polymer compound is designated as polymer 13.

[Synthesis Example 14]
9.5 g of monomer 2, 9.7 g of 4-acetoxystyrene, 3.4 g of PAG monomer 3, 0.5 g of indole, and 40 g of tetrahydrofuran as a solvent were added to a 2 L flask. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: 4-hydroxystyrene: PAG monomer 3: Indole = 0.30: 0.60: 0.06: 0.04
Weight average molecular weight (Mw) = 7,300
Molecular weight distribution (Mw / Mn) = 1.72
This polymer compound is designated as polymer 14.

[Synthesis Example 15]
To a 2 L flask, 9.5 g of monomer 2, 9.7 g of 4-acetoxystyrene, 3.4 g of PAG monomer 3, 0.6 g of 2-dimethylaminoethyl methacrylate, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: 4-hydroxystyrene: PAG monomer 3: 2-dimethylaminoethyl methacrylate = 0.30: 0.60: 0.06: 0.04
Weight average molecular weight (Mw) = 7,300
Molecular weight distribution (Mw / Mn) = 1.66
This polymer compound is designated as polymer 15.

[Synthesis Example 16]
9.5 g of monomer 2, 9.7 g of 4-acetoxystyrene, 3.4 g of PAG monomer 3, 0.9 g of indole-1-t-butoxycarbonyl, and 40 g of tetrahydrofuran as a solvent were added to a 2 L flask. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: 4-hydroxystyrene: PAG monomer 3: Indole-1-t-butoxycarbonyl = 0.30: 0.60: 0.06: 0.04
Weight average molecular weight (Mw) = 8,100
Molecular weight distribution (Mw / Mn) = 1.70
This polymer compound is designated as polymer 16.

[Synthesis Example 17]
In a 2 L flask, 9.5 g of monomer 2, 3.6 g of 4-hydroxyphenyl methacrylate, 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonane-9 methacrylate -8.0 g of yl, 6.7 g of PAG monomer 4, 0.7 g of 2-morpholinoethyl methacrylate, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution was precipitated in 1 L of isopropyl alcohol, and the resulting white solid was filtered and dried under reduced pressure at 60 ° C. to obtain a white polymer.
When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: 4-hydroxyphenyl methacrylate: 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonan-9-yl methacrylate: PAG monomer 4: methacrylate-2 -Morpholinoethyl = 0.30: 0.20: 0.36: 0.10: 0.04
Weight average molecular weight (Mw) = 7,900
Molecular weight distribution (Mw / Mn) = 1.82
This polymer compound is designated as polymer 17.

[Synthesis Example 18]
In a 2 L flask, 9.5 g of monomer 2, 3.6 g of 4-hydroxyphenyl methacrylate, 3-oxo-2,7-dioxatricyclomethacrylate [4.2.1.0 ^4,8 ] nonane-9 -8.0 g of yl, 5.2 g of PAG monomer 5, 0.7 g of 2-morpholinoethyl methacrylate, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution was precipitated in 1 L of isopropyl alcohol, and the resulting white solid was filtered and dried under reduced pressure at 60 ° C. to obtain a white polymer.
When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: 4-hydroxyphenyl methacrylate: 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonan-9-yl methacrylate: PAG monomer 5: methacrylic acid-2 -Morpholinoethyl = 0.30: 0.20: 0.36: 0.10: 0.04
Weight average molecular weight (Mw) = 7,600
Molecular weight distribution (Mw / Mn) = 1.87
This polymer compound is designated as polymer 18.

[Synthesis Example 19]
In a 2 L flask, 9.5 g of monomer 2, 3.6 g of 4-hydroxyphenyl methacrylate, 3-oxo-2,7-dioxatricyclomethacrylate [4.2.1.0 ^4,8 ] nonane-9 -8.7 g of yl, 7.4 g of PAG monomer 6, 0.7 g of 2-morpholinoethyl methacrylate, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution was precipitated in 1 L of isopropyl alcohol, and the resulting white solid was filtered and dried under reduced pressure at 60 ° C. to obtain a white polymer.
When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: 4-hydroxyphenyl methacrylate: 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonan-9-yl methacrylate: PAG monomer 6: methacrylate-2 -Morpholinoethyl = 0.30: 0.20: 0.36: 0.10: 0.04
Weight average molecular weight (Mw) = 8,300
Molecular weight distribution (Mw / Mn) = 1.91
This polymer compound is referred to as polymer 19.

[Synthesis Example 20]
In a 2 L flask, 9.5 g of monomer 2, 5.5 g of 5-hydroxyindan-2-yl methacrylate, 3-oxo-2,7-dioxatricyclo methacrylate [4.2.1.0 ^4,8 6.7 g of nonan-9-yl, 5.7 g of PAG monomer 3, 0.2 g of t-butoxycarbonylvinylamine, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution was precipitated in 1 L of isopropyl alcohol, and the resulting white solid was filtered and dried under reduced pressure at 60 ° C. to obtain a white polymer.
When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: 5-hydroxyindan-2-yl methacrylate: 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonan-9-yl methacrylate: PAG monomer 3: t-butoxycarbonylvinylamine = 0.30: 0.25: 0.30: 0.10: 0.05
Weight average molecular weight (Mw) = 7600
Molecular weight distribution (Mw / Mn) = 1.72
This polymer compound is referred to as polymer 20.

[Synthesis Example 21]
9.5 g of monomer 2, 1.1 g of acenaphthylene, 8.9 g of 4-acetoxystyrene, 3.0 g of PAG monomer 2, 0.4 g of 5-hydroxyindole, and 40 g of tetrahydrofuran as a solvent were added to a 2 L flask. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: Acenaphthylene: 4-hydroxystyrene: PAG monomer 2: 5-hydroxyindole = 0.30: 0.07: 0.55: 0.05: 0.03
Weight average molecular weight (Mw) = 6,100
Molecular weight distribution (Mw / Mn) = 1.63
This polymer compound is referred to as polymer 21.

[Synthesis Example 22]
9.5 g of monomer 2, 1.0 g of indene, 8.9 g of 4-acetoxystyrene, 3.0 g of PAG monomer 2, 0.4 g of 5-nitroindole, and 40 g of tetrahydrofuran as a solvent were added to a 2 L flask. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: Indene: 4-Hydroxystyrene: PAG Monomer 2: 5-Nitroindole = 0.30: 0.08: 0.54: 0.05: 0.03
Weight average molecular weight (Mw) = 6,400
Molecular weight distribution (Mw / Mn) = 1.64
This polymer compound is designated as polymer 22.

[Synthesis Example 23]
9.5 g of monomer 2, 1.1 g of benzofuran, 8.9 g of 4-acetoxystyrene, 2.8 g of PAG monomer 3, 0.3 g of 5-aminomethylindole, and 40 g of tetrahydrofuran as a solvent were added to a 2 L flask. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: Benzofuran: 4-hydroxystyrene: PAG monomer 3: 4-hydroxyindole = 0.30: 0.08: 0.55: 0.05: 0.02
Weight average molecular weight (Mw) = 6,800
Molecular weight distribution (Mw / Mn) = 1.61
This polymer compound is referred to as polymer 23.

[Synthesis Example 24]
9.5 g of monomer 2, 1.1 g of benzothiophene, 8.9 g of 4-acetoxystyrene, 2.8 g of PAG monomer 3, 0.4 g of 4-hydroxyindole, and 40 g of tetrahydrofuran as a solvent were added to a 2 L flask. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: Benzofuran: 4-hydroxystyrene: PAG monomer 3: 4-hydroxyindole = 0.30: 0.08: 0.54: 0.05: 0.03
Weight average molecular weight (Mw) = 6,800
Molecular weight distribution (Mw / Mn) = 1.61
This polymer compound is designated as polymer 24.

[Synthesis Example 25]
9.5 g of monomer 2, 1.1 g of benzothiophene, 8.9 g of 4-acetoxystyrene, 1.8 g of PAG monomer 7, 0.4 g of 4-hydroxyindole, and 40 g of tetrahydrofuran as a solvent were added to a 2 L flask. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: Benzothiophene: 4-hydroxystyrene: PAG monomer 7: 4-hydroxyindole = 0.30: 0.08: 0.54: 0.05: 0.03
Weight average molecular weight (Mw) = 6,800
Molecular weight distribution (Mw / Mn) = 1.61
This polymer compound is designated as polymer 25.

[Synthesis Example 26]
9.5 g of monomer 2, 1.1 g of benzothiophene, 8.9 g of 4-acetoxystyrene, 1.9 g of PAG monomer 8, 0.4 g of 4-hydroxyindole, and 40 g of tetrahydrofuran as a solvent were added to a 2 L flask. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 2: Benzofuran: 4-hydroxystyrene: PAG monomer 8: 4-hydroxyindole = 0.30: 0.08: 0.54: 0.05: 0.03
Weight average molecular weight (Mw) = 6,800
Molecular weight distribution (Mw / Mn) = 1.61
This polymer compound is designated as polymer 26.

[Synthesis Example 27]
To a 2 L flask, 9.2 g of monomer 7, 1.1 g of benzothiophene, 8.9 g of 4-acetoxystyrene, 2.8 g of PAG monomer 3, 0.4 g of 4-hydroxyindole, and 40 g of tetrahydrofuran as a solvent were added. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 7: Benzofuran: 4-hydroxystyrene: PAG monomer 3: 4-hydroxyindole = 0.30: 0.08: 0.54: 0.05: 0.03
Weight average molecular weight (Mw) = 6,600
Molecular weight distribution (Mw / Mn) = 1.85
This polymer compound is referred to as polymer 27.

[Synthesis Example 28]
To a 2 L flask was added 9.7 g of monomer 8, 1.1 g of benzothiophene, 8.9 g of 4-acetoxystyrene, 2.8 g of PAG monomer 3, 0.4 g of 4-hydroxyindole, and 40 g of tetrahydrofuran as a solvent. The reaction vessel was cooled to −70 ° C. in a nitrogen atmosphere, and vacuum degassing and nitrogen blowing were repeated three times. After raising the temperature to room temperature, 1.2 g of AIBN (azobisisobutyronitrile) was added as a polymerization initiator, and the temperature was raised to 60 ° C. and reacted for 15 hours. This reaction solution is precipitated in 1 L of isopropyl alcohol, and the resulting white solid is dissolved again in 100 mL of methanol and 200 mL of tetrahydrofuran. 10 g of triethylamine and 10 g of water are added, and the acetyl group is deprotected at 70 ° C. for 5 hours. And neutralized with acetic acid. The reaction solution was concentrated and then dissolved in 100 mL of acetone, followed by precipitation, filtration and drying at 60 ° C. as described above to obtain a white polymer. When the obtained polymer was measured by ¹³ C, ¹ H-NMR and GPC, the following analysis results were obtained.
Copolymer composition ratio (molar ratio)
Monomer 8: Benzofuran: 4-hydroxystyrene: PAG monomer 3: 4-hydroxyindole = 0.30: 0.08: 0.54: 0.05: 0.03
Weight average molecular weight (Mw) = 6,800
Molecular weight distribution (Mw / Mn) = 1.74
This polymer compound is referred to as polymer 28.

The monomers 1 to 8 and PAG monomers 1 to 8 used in Synthesis Examples 1 to 28 are shown below.

[Comparative Synthesis Example 1]
4-t-butoxystyrene: 4-hydroxystyrene: methacrylic acid 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonan-9-yl: PAG monomer 3 = 0. 30: 0.47: 0.15: 0.08
Weight average molecular weight (Mw) = 8,900
Molecular weight distribution (Mw / Mn) = 1.90
This polymer compound is referred to as comparative polymer 1.

[Comparative Synthesis Example 2]
4-t-butoxystyrene: 4-hydroxystyrene: 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonan-9-yl methacrylate: 1-vinylimidazole = 0 .30: 0.51: 0.15: 0.04
Weight average molecular weight (Mw) = 8,900
Molecular weight distribution (Mw / Mn) = 1.93
This polymer compound is referred to as comparative polymer 2.

[Comparative Synthesis Example 3]
4-t-butoxystyrene: 4-hydroxystyrene: 3-oxo-2,7-dioxatricyclo [4.2.1.0 ^4,8 ] nonan-9-yl methacrylate = 0.30: 0. 50: 0.20
Weight average molecular weight (Mw) = 9,200
Molecular weight distribution (Mw / Mn) = 1.99
This polymer compound is referred to as comparative polymer 3.

[Examples 1-30, Comparative Examples 1-3]
Using the polymer compound synthesized above, a solution obtained by dissolving FC-4430, a surfactant manufactured by 3M, as a surfactant in a solvent in which 100 ppm is dissolved with a composition shown in Table 1, is 0.2 μm in size. The positive resist material was prepared by filtering with a filter.
Each composition in Table 1 is as follows.
Polymers 1-28: Synthesis Examples 1-28
Comparative polymers 1-3: Comparative synthesis examples 1-3
Organic solvent: PGMEA (propylene glycol monomethyl ether acetate)
CyH (cyclohexanone)
PGME (propylene glycol monomethyl ether)
Acid generator: PAG1 (see structural formula below)
Basic compounds: Amine 1 and Amine 2 (see the structural formula below)

Electron beam drawing evaluation The resist material shown in Table 1 was spin-coated on a 6-inch diameter Si substrate using a clean track Mark 5 (manufactured by Tokyo Electron), and prebaked at 110 ° C. for 60 seconds on a hot plate. An 80 nm resist film was prepared. For this, drawing in a vacuum chamber was performed at an HV voltage of 50 keV using a Hitachi HL-800D.
Immediately after drawing, post-exposure baking (PEB) is performed on a hot plate for 60 seconds using a clean track Mark 5 (manufactured by Tokyo Electron), paddle development is performed for 30 seconds with a 2.38 mass% TMAH aqueous solution, Got a pattern.
The obtained resist pattern was evaluated as follows.
The minimum dimension at the exposure amount for resolving 120 nm line and space at 1: 1 was taken as the resolving power, and 120 nm LS edge roughness was measured by SEM.
Table 1 shows the resist composition and the results of sensitivity, resolution, and edge roughness in EB exposure.

From the results in Table 1, it was found that the resist material of the present invention has sufficient resolution and appropriate sensitivity, and the edge roughness is sufficiently small.
On the other hand, although the resist material of the comparative example has sufficient resolution and sensitivity, the edge roughness was considerably larger than that of the resist material of the present invention.

  That is, as a polymer compound constituting the resist material, as in the resist material of the present invention, a copolymer obtained by copolymerizing a repeating unit having an acid labile group, a polymer type acid generator, and a polymer type amine compound. If it is included, it can be said that it can be used very effectively as a resist material for VLSI, a mask pattern forming material, and the like because it has high resolution, high sensitivity, and low line edge roughness.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

Claims (7)

At least one of repeating unit a having a phenolic hydroxyl group substituted with an acid labile group represented by the following general formula (1), repeating unit b1 and b2 having a sulfonium salt, repeating having an amino group A resist material comprising a polymer compound having a unit c.

(In the formula, R ¹ , R ³ , R ⁸ and R ¹² each independently represents a hydrogen atom, a methyl group, a fluorine atom or a trifluoromethyl group. R ² represents an acid labile group. R ⁴ represents an alkylene group or an arylene group having 6 to 10 carbon atoms having 1 to 10 carbon atoms, a fluorine atom, a trifluoromethyl group, an ester group, an ether group, which may have a lactone ring ^{.R 5, R} 6, R ⁷ , R ⁹ , R ¹⁰ and R ¹¹ are the same or different, linear, branched or cyclic alkyl groups having 1 to 12 carbon atoms, and may contain a carbonyl group, an ester group or an ether group. Or an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or a thiophenyl group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group, an alkoxycarbonyl group, a carbonate group, and May have a gen atom, a cyano group, a hydroxyl group, or a carboxyl group as a substituent, Y is a single bond, an methylene group, an arylene group substituted with a fluorine atom or a trifluoromethyl group, -C (= O) ^{-O-R 17} - is ^{.R 17} is fluorine atom or a substituted arylene group a trifluoromethyl group ^{.R 13} is a single bond or a straight, branched or cyclic alkylene ^group, R ^{14, R 15} are each independently a hydrogen atom, C 1 -C 20 straight, branched or cyclic alkyl group, t-butoxycarbonyl group, or t-a Mi butyloxycarbonyl group, an ether May have a bond, a thioether bond, a hydroxyl group, a formyl group, an acetoxy group, a cyano group or an aromatic group, and R ¹³ and R ¹⁴ , R ¹³ and R ¹⁵ R ¹⁴ and R ¹⁵ may be bonded to form a ring, R ¹⁶ may be bonded to a hydrogen atom or R ¹⁵ to form a ring, and Z is a single bond, methylene group, arylene. A group, —O—, —C (═O) —O— or —C (═O) —O—R ¹⁸ —C (═O) —O—, wherein R ¹⁸ is a single bond or 1 carbon atom. A linear, branched or cyclic alkylene group of from 0 to 10. 0 <a <1.0, 0 ≦ b1 ≦ 0.3, 0 ≦ b2 ≦ 0.3, 0 <b1 + b2 ≦ 0.3, 0 <C ≦ 0.5.)   The resist material according to claim 1, wherein the resist material is a chemically amplified positive resist material.   3. The resist material according to claim 1, wherein the resist material contains one or more of an organic solvent, a dissolution inhibitor, an acid generator, a basic compound, and a surfactant. Resist material.   At least a step of applying the resist material according to any one of claims 1 to 3 on a substrate, a step of exposing to high energy rays after heat treatment, and a step of developing using a developer. A pattern forming method comprising:   5. The pattern forming method according to claim 4, wherein in the step of exposing with the high energy beam, vacuum ultraviolet rays having a wavelength of 3 to 15 nm are used as a light source.   5. The pattern forming method according to claim 4, wherein an accelerating voltage electron beam having an accelerating voltage of 50 keV or less is used as a light source in the step of exposing with the high energy beam.   The pattern forming method according to claim 6, wherein the acceleration voltage electron beam is a low acceleration voltage electron beam having an acceleration voltage of 10 keV or less.